Add start/stop workflows and move to environment-based config

- Add start.yml and stop.yml workflows for server lifecycle
- All workflows now use `type: environment` input for environment selection
- Secrets and variables moved from repo-level to environment-level
- Enables approval gates per environment (e.g., require approval for production)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

.github/workflows/check-update.yml

@@ -1,14 +1,18 @@
 name: Check Deployed Version
 
 on:
-  schedule:
-    - cron: '0 8 * * 1' # Weekly on Monday at 8 AM UTC
   workflow_dispatch:
+    inputs:
+      environment:
+        description: 'Target environment'
+        type: environment
+        required: true
 
 jobs:
   check:
-    name: 'Check deployed version'
+    name: 'Check version (${{ inputs.environment }})'
     runs-on: ubuntu-latest
+    environment: ${{ inputs.environment }}
 
     steps:
       - name: Check current deployed version
@@ -22,8 +26,9 @@ jobs:
           BASE_DIR="${{ vars.BASE_DIR || './sfp-server' }}"
 
           if [ -z "$SSH_HOST" ] || [ -z "$SSH_PRIVATE_KEY" ]; then
-            echo "SSH not configured, cannot check deployed version"
+            echo "SSH not configured for environment '${{ inputs.environment }}'"
             echo "current_tag=unknown" >> $GITHUB_OUTPUT
+            echo "current_fqdn=unknown" >> $GITHUB_OUTPUT
             exit 0
           fi
 
@@ -51,7 +56,7 @@ jobs:
           CONFIGURED_TAG="${{ vars.IMAGE_TAG || 'latest' }}"
           CONFIGURED_FQDN="${{ vars.IMAGE_FQDN }}"
 
-          echo "## SFP Server Version Status" >> $GITHUB_STEP_SUMMARY
+          echo "## SFP Server Version Status (${{ inputs.environment }})" >> $GITHUB_STEP_SUMMARY
           echo "" >> $GITHUB_STEP_SUMMARY
           echo "| | Image | Tag |" >> $GITHUB_STEP_SUMMARY
           echo "|---|-------|-----|" >> $GITHUB_STEP_SUMMARY
@@ -60,7 +65,7 @@ jobs:
 
           if [ "$CURRENT_TAG" != "$CONFIGURED_TAG" ] && [ "$CURRENT_TAG" != "unknown" ]; then
             echo "" >> $GITHUB_STEP_SUMMARY
-            echo "Deployed version differs from configured version. Run the **Update SFP Server** workflow to update." >> $GITHUB_STEP_SUMMARY
+            echo "Deployed version differs from configured. Run **Update SFP Server** to update." >> $GITHUB_STEP_SUMMARY
           elif [ "$CURRENT_TAG" = "unknown" ]; then
             echo "" >> $GITHUB_STEP_SUMMARY
             echo "Could not determine currently deployed version." >> $GITHUB_STEP_SUMMARY